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Models 400 and 410
This section provides a description of the system unit module components
for Models 400 and 410. These components are accessed from the bottom of
the computer:
o Hard drive -- The hard drive is easily replaced or upgraded from the
bottom of the computer. Remove two screws from the hard drive
compartment cover to access the hard drive. The hard drive mounts to the
system chassis with a hard drive bracket and connects directly to the
system board with no intervening cables. The hard drive bracket attaches
to the hard drive with four screws.
o Memory expansion -- System memory can be upgraded with optional memory
expansion boards. An expansion board is added or replaced from the
bottom of the computer through the memory compartment cover. The memory
expansion board connects directly to the system board with two
connectors.
o Battery pack -- The Nickel Metal Hydride battery pack is accessed
through the battery compartment.
To access the remaining system unit components, open the computer and
remove the keyboard assembly. These components include the following:
o Integrated trackball assembly -- The mechanical trackball is centrally
located at the bottom of the keyboard assembly. The assembly consists of
the trackball, retaining ring, and connector. The trackball assembly
connects directly to the system board and is secured by one screw. It
cannot be replaced with the optical trackball used in the Models 420 and
430. The mechanical trackball and optical trackball are not
interchangeable.
o System board -- The system board is mounted directly to the system
chassis. All removable components connected to the system board, except
for the PC Card rails, must be removed prior to removing the system
board. The system board is unique and cannot be replaced by the one
used in the Models 420 and 430.
o Processor upgrade -- Systems that come with the DX2/40 MHz processor can
be upgraded to the DX2/50 MHz processor. Place the upgrade processor into
the two connectors on the system board (Refer to "Removal and
Replacement Procedures, Section 3.11). Once installed, the processor
overrides control of the system board processor. The system board
processor is not removable.
o Real-Time Clock Battery -- This battery is located directly behind the
Trackball.
o PC Card rails -- The PC Card rails are replaceable and are secured by
two screws from the bottom of the system board and a clip on top of the
rails. The rails are not interchangeable with those used in Models 420
and 430. The clip is common between all models. The header attaches
directly to the system board and cannot be removed. The top and bottom